Numerous cosmetics exist for treatment and concealment of wrinkles. The problem of how to alleviate wrinkling and improve the health and appearance of wrinkled skin is ubiquitous and cosmetic methods for treatment of wrinkles are avidly sought.
In previous publication WO 03049706 (WO '706) one of the inventors of describes an aqueous liquid or emulsion comprising: water; hydrophilic particles consisting of oxide particles having surfaces covered with polar radicals; and hydrophobic particles; wherein the hydrophilic and hydrophobic particles form shells encapsulating a gas that are suspended in the water, said shells comprising an external layer of hydrophilic particles and an internal layer of hydrophobic particles adjacent to the layer of hydrophilic particles. The WO '706 further describes a powder comprising: water; hydrophilic oxide particles; and hydrophobic oxide particles; wherein the water is encapsulated in shells comprising an external layer of hydrophobic oxide particles and an internal layer of hydrophilic oxide particles adjacent to the layer of hydrophobic oxide particles. There are no amphiphilic particles in this aqueous liquid or emulsion composition.
WO '706 specifically refers to diameters of hydrophilic and hydrophobic nano-particles that range from about 5 nm to about 150 nm (page 9, lines 1-2). It further indicates that hydrophilic particles and hydrophobic particles preferably have a specific surface (i.e. surface to mass ratio) that is greater than about 100 m2/g and preferably substantially greater. It is advantageous for hydrophilic and hydrophobic particles to be as small as possible and to the extent that the specific surface of a particle is greater, the size of the particle is smaller (page 9, lines 12-16).
US 20060257437 of one of the inventors of present invention relates to a topical cosmetic composition which comprises water, hydrophobic nano-particles (preferably hydrophobic silica), and hydrophilic nano-particles (preferably hydrophilic silica), and a soluble electrolyte, capable of releasing free ions in an aqueous environment. In the presence of hydrophilic and hydrophobic nano-particles, the composition simultaneously comprises bounded shells encapsulating a gaseous material, dispersed in water and bounded shells encapsulating aqueous solution droplets. More specifically, the bounded shells encapsulating gas are coated by an external layer of hydrophilic nano-particles and an internal layer of hydrophobic nano-particles and the bounded shells encapsulating aqueous solution droplets are coated by an external layer of hydrophobic nano-particles and an internal layer of hydrophilic nano-particles. There are no amphiphilic particles in this composition.
The inventors of present invention further relate in IL 192201 to a two-phase skin-care composition, which simultaneously comprises separate, immiscible, stable hypotonic and hypertonic phases, relatively to the skin, wherein at least one phase consists of a plurality of separate, immiscible, stable hypertonic or hypotonic entities. Applying said composition onto the skin resulted in multidirectional movement of ions from multiple, individual hypertonic entities into the skin, yielding a heterogeneous electrical field in the treated skin area with a substantial higher potential gradient, side by side with multidirectional flow of fluid, containing water and optionally skin-care ingredients, from the multiple, individual hypotonic entities towards hypertonic ones and the skin. The separate, immiscible, stable hypotonic and/or hypertonic entities are bounded water (or aqueous suspension) droplets having internal layer(s) of hydrophilic nano-particles and external layer(s) of hydrophobic nano-particles. There are no amphiphilic particles in this two-phase composition.
The brochure by Arkema (“Orgasol—New Senses for Skin Care”) and U.S. Pat. No. 8,287,950 describe the skin care product Orgasol® Caresse which comprises round shaped uniformed amphiphilic polyamide or copolyesteramide micro-particles having average particle size of 10 μm (specific surface area: about 8 m2/g). During the production of said amphiphilic micro-particles, Aerosil® R 972 (hydrophobic fumed silica with a pH of between 3.6 and 4.4, composed of individual primary particles with a diameter of 16 nm, which have a tendency to agglomerate into larger particles, and with a specific surface of 110 m2/g (ISO 5794-1)). This silica which was subjected to a hydrophobic treatment using dimethylsilyl or trimethylsilyl groups, was used as a filler. After filtering off and drying, a polyamide-12 powder is obtained which is composed of spheroidal particles. These amphiphilic micro-particles having hydrophilic-hydrophobic balance that makes their dispersion easy in oil/water emulsions.
None of WO '706, US 20060257437 and IL 192201 refer to an aqueous suspension or emulsion that comprises said combination of air, individual hydrophobic and hydrophilic metal (and/or silicon) oxide nano-particles, and at least one type of amphiphilic micro-particles having diameters in the range of 1-100 μm.